鈦金屬及其合金已廣泛應用在生醫材料上，藉由其良好的生物相容性，當鈦金屬與空氣或體液接觸時，其高活性會促使表面形成一厚度為數奈米的氧化層，當骨母細胞貼附於氧化層上，會與氧化層產生活性鍵結，並進行增生與分化之途徑，此過程亦稱為骨整合 (osseointegration)。研究指出，在平滑的鈦金屬表面，骨母細胞生長將受限於其低表面積，故學者利用表面改質方式增加細胞親和性。本研究中，利用自組裝單層膜改質二氧化鈦奈米管陣列表面，藉由調控奈米管之成管條件與自組裝單層膜的不同的末端官能基的影響，觀察人類骨肉瘤細胞株 (HOS, human osteosarcoma cell lines)的生長行為，期望能調控細胞的生長與反應。
實驗中，於二氧化鈦奈米管的生成，主要的關鍵在於HF與F-的濃度。HF的解離性不佳，在陽極氧化過程，若是無法提供足夠的F-離子，奈米管結構將無法顯現。解決的方法有二，一是藉由額外添加可增進HF解離的藥品，如NaOH等等，一是改善反應器的導電能力，如加大陰極電極，都可以促進反應的發生。於自組裝單層膜上，利用浸泡的方式長成，由接觸角試驗得知，有利用氧電漿處理的表面，其接觸角較沒有經過氧電漿處理而直接進行接枝的表面來得大，表示氧電漿有促進自組裝單層膜於表面改質的能力。於細胞實驗中，可以發現短時間的細胞形態，除平坦表面的細胞生長速度較慢外，其他有奈米管的表面，對於細胞的黏附都有增強的效果，是否是奈米管對細胞生長的效果較自組裝單層膜對細胞的影響顯著而造成的現象，將可以用細胞增生實驗與細胞份化實驗得知。

Titanium and its alloys are widely used in biomaterials because of their good biocompatibility. When titanium was contact with the air or fluids, the high activities of Ti would drive the surface to forming a several nm thickness oxide layer. Osteoblast cells would lead to the pathway of proliferation and differentiation by adhered to the oxide layer, forming active bindings. The process is also called osseointegration. It had found that the flat Ti surface limited osteoblast cells to growth because of the low surface area. To prove the problem, surface modification is used to increase cell adaptation. The aim of the study is to use the self- assembly monolayers (SAMs) modified TiO2 nanotubes array surface to observed the HOS growth behaviors by modulated the nanotube-forming factors and the different functional end group SAM.
The key factor of the TiO2 nanotube formation is the concentration of HF and F . The acid dissociation constant of HF is not high enough to forming the TiO2 nanotubes in the anodic oxidation process with lower [F-]. To increase the [F-], NaOH, which can dissociate HF, and boarding Pt cathode electrode, are both the good ideas. The SAMs were formed by immersion. By contact angle test, the use of RF O2 plasma treatment has the ability to enhance the grafting of SAMs with higher contact angle. In the in vitro test, surface with nanotubes was good for cell to adhesion except the flat surface. To understand cell growth behavior by the surface of TiO2 nanotubes with SAM, cell proliferation and differentiation test could accurately proved.

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